I am experiencing an issue with UI for Blazor's SplitButton. When I click on the dropdown arrow initially, it correctly expands the dropdown list area. However, while the dropdown list area is expanded, if I click the arrow again, it does not close it, leaving the dropdown list area expanded. The exact behavior appears to be that the dropdown collapses while the mouse is pressed down over the arrow button, but when the mouse is released, the dropdown list area expands again.

Reproduction: https://blazorrepl.telerik.com/QnlPPdvv50aUXSKO14.

The desired behavior is that the split button arrow would toggle the dropdown list between expanded and collapsed states.